What volume of KOH solution with a mass fraction of 12% (p = 1.11 g / cm3) should be taken

What volume of KOH solution with a mass fraction of 12% (p = 1.11 g / cm3) should be taken to prepare 250 cm3 of a 2M solution?

The amount of alkali in 250 ml of a 2M solution is 0.25 x 2 = 0.5 mol;

Let’s calculate the weight of this amount of alkali.

M KOH = 40 + 16 + 1 = 57 grams / mol;

m KOH = 57 x 0.5 = 28.5 grams;

The mass of a 12% alkali solution containing such a mass of alkali is:

M solution = 28.5 / 0.12 = 237.5 grams;

Its volume will be:

V solution = 237.5 / 1.11 = 213.96 ml;